Question: Simplify the expression. $(r^{4}+2r^{3}+7r^{2})(7r^{3})$
Solution: First use the distributive property. $ r^4 (7 r^3) + 2 r^3 (7 r^3) + 7 r^2 (7 r^3) $ Simplify. $7r^{7}+14r^{6}+49r^{5}$